HIBIYA Toshiyuki


日比谷 紀之ひびや としゆき
HIBIYA Toshiyuki

HIBIYA Toshiyuki
Title Professor
Affiliation Department of Earth and Planetary Physics (UG), Department of Earth and Planetary Science (GR), Graduate School of Science
E-mail
Room 814, Faculty of Science Bldg.1, 8F
TEL +81-3-5841-4303 | 24303(ext.)


Research Field

Ocean Dynamics

Research Subject

Parameterization of diapycnal mixing processes in the deep ocean for next-generation global circulation models, Dynamics of the Kuroshio meander.

Current Research

One of the activities my research group is enthusiastically pursuing is the global mapping of diapycnal mixing intensity in the deep ocean to improve the ability of meridional overturning circulation models in predicting future climate changes. On the basis of detailed numerical experiments as well as field observations using expendable current profilers (XCPs) and microstructure profilers (MSPs), we have found that the diapycnal mixing intensity is strongly latitude-dependent where mixing hotspots are limited to prominent topographic features at latitudes 20˚-30˚ where the available semidiurnal internal tide energy can be efficiently transferred to dissipation scales by parametric subharmonic instability. Other activities of my research group includes the numerical simulation of the transient response of the Kuroshio leading to the large meander formation using a three-dimensional, primitive equation numerical model that takes into account realistic topography.

Keywords

Turbulence, Diffusivity, Mixing, Deep Ocean, Parameterization, Meridional Overturning Circulation, Tides, Internal Gravity Waves, Nonlinear Wave Interactions, Energy Cascades, Near-Inertial Shear, Kuroshio, Numerical Experiments, Baroclinic Instability

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